静電相互作用は,リボソームからの極端な新生タンパク質放出時間を制御し,リボソームのリサイクルを遅らせることができます
Daniel A Nissley, Quyen V Vu1, Fabio Trovato
1Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw, Poland.
Journal of the American Chemical Society
|March 7, 2020
まとめ
リボソームからのタンパク質放出は,電荷によって大きく変化します. 誘導力による緩やかな放出は,リボソームの循環を遅らせ,リボソームタンパク質のコトランスレーションアセンブリを助長する.
科学分野:
- 分子生物学
- バイオ物理学
- コンピュータ生物学
背景:
- リボソームの出口トンネルから新生タンパク質の放出プロセスは,実験的に難しいままです.
- この過程を理解することは,タンパク質合成と共翻訳現象を理解するために極めて重要です.
研究 の 目的:
- リボソームから新生タンパク質の放出時間に影響を与える要因を調査する.
- タンパク質の配列と 放出ダイナミクスの関係と リボソームのリサイクルといった 細胞のプロセスを調べる
主な方法:
- マルチスケールモデリングとタンパク質放出のシミュレーション
- バイオダイナミクスを分析する *E. coli* のリボソームプロファイリング
- 配列特性を機能と相関させるための遺伝子本体分析.
主要な成果:
- シミュレートされた *E. coli* タンパク質のエジェクション時間は1000倍以上変化しました.
- 負の電荷のC端は放出を加速し,正の電荷のC端は放出を遅らせる.
- リボソームの停留時間の増加と相関し,リサイクルが遅れていることを示唆しています.
結論:
- 異なる静電相互作用が新生タンパク質の放出速度を制御する.
- 射出ダイナミクスはリボソームのリサイクル効率に影響を与えます.
- 配列依存のエジェクションは,特にリボソームタンパク質のコトランスレーションアセンブリにおいて役割を果たす可能性があります.
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